In recent years, a communication apparatus such as a smartphone and a mobile phone has been spread worldwide, and a wearable device (device which can be used while being worn by a user) such as a wristwatch-type device and a glasses-type device has been actively developed. Further, a technology relating to reduction of a specific absorption rate (SAR) has been developed. Examples of the technology relating to reduction of a SAR can include a technology disclosed in the following Patent Literature 1.